1. Field of the Invention
This invention relates to the field of network communications. In particular, the present invention relates to an efficient communications network quality of service system and method for real time information.
2. Related Art
Electronic devices and systems have made a significant contribution towards the advancement of modern society and are utilized in a number of applications to achieve advantageous results. Numerous electronic technologies such as digital computers, calculators, audio devices, video equipment, and telephone systems have facilitated increased productivity and reduced costs in analyzing and communicating data, ideas and trends in most areas of business, science, education and entertainment. These advantageous results are often realized and maximized through the use of distributed resources (e.g., electronic devices) that communicate via a network. The distributed resources are often end use devices (e.g., a personal computer, video device, telephone, etc.) coupled to a communications network and rely on information communicated over the network in the performance of their prescribed tasks (e.g., internet interface, movie presentation, or communication of a conversation). The quality of service a network management system and method provides often has a significant impact on the performance of the end use devices.
There are numerous different communications networks that transfer information in a variety of implementations. Typically a network is defined by its attributes and abilities such as the type of communication medium used (e.g., copper wires, fiber optics, coax cable, radio waves, microwaves, etc.), the cable layout (or topology), data transfer rates, communication protocols, and the method used by nodes to access and use the network (access methods). Usually there are a number of end use devices (e.g., personal computers, telephones, etc.) that are coupled together by communication mediums which convey information to a destination with the assistance of intermediate control devices (e.g., bridges, routers, gateways, switches, repeaters, cellular base stations, satellites, etc.). Some of the most popular types of networks comprise Ethernet (coaxial cable or twisted-pair cable), token ring, Fiber Distributed Data Interface (FDDI), Frame Relay, Integrated services Digital Network (ISDN), X.25, Synchronous Data Link Control (SDLC), high speed networks such as ATM and wireless (e.g., cellular telephony).
Quality of service measurements indicate a level of network performance criteria. There are usually a number of network characteristics that impact quality of service levels. For example, quality of service is often expressed in terms of latency requirements. Latency is the time delay involved in moving data traffic through a network. Several items affect latency including propagation delays, transmission delays and switching processing delays. Another important network attribute that impacts quality of service is bandwidth. Bandwidth is the amount of information that a network is capable of transmitting in a given period and the amount of bandwidth available is typically limited by network resources.
Generally, communication network resources are relatively expensive and it is not economical to build a network with enough bandwidth to instantaneously handle all possible information transmission requests under worst case scenarios. Communication networks built with the ability to handle the maximum possible communication load that all the end use and intermediate network devices could generate if they all tried to access the network at one time are usually inefficient. Therefore, most communication networks are built with limited resources and even though limiting communication network resources is economically efficient in many instances it does give rise to the need for a network management protocol to determine which of the limited network resources are utilized at what time for a communication of information.
Traditional network management protocols are often inadequate and do not provide effective quality of service. One type of buffer and forward traditional network management approach involves giving greater priority to some information and randomly dropping information if the buffers are full. While these approaches provide some quality or service benefits they also have significant detrimental side affects. For example, giving relatively greater priority to some information does not guarantee the information is going to arrive at its final destination in a timely manner (e.g., real time data arrives in real time) and not getting the information to its final destination in a timely manner frequently means the information is useless. Nevertheless, prior art approaches often buffer the information for later transmission and utilize bandwidth resource to transmit what is essentially useless information depriving useful information of that bandwidth.
The quality of service provided by a network management system and method usually has a significant impact on the performance of end use devises. To perform a particular task adequately typically requires a minimum quality of service. For example, if there is to much latency in some application transmission (e.g., a video presentation or voice communications) the user is not able to perceive (e.g., hear or perceive) an even stream of data. Not being able to receive a relatively even stream of data significantly impacts the practical benefits of the communications network. For example, if a voice conversation or a video presentation gets so choppy that a person can not understand what is being said or presented the communication is essentially useless from a practical standpoint.
One of the most common and prolific distributed resource systems that communicates real time information includes numerous inter-networked computers communicatively coupled together to form the Internet. Typically, computers coupled to the Internet communicate in a Transmission Control Protocol/Internet Protocol (TCP/IP), which divides information into packets and routes them to their destination identified by an IP address. Real time information and applications are prolifically distributed on the Internet. For example, player versus player video games users typically require real time information for the users to enjoy maximized pleasure of playing a game. The players typically make moves in response to moves by an opponent and if information is not real time the challenge of fast pass move and counter moves is significantly diminished or lost.
What is required is a system and method that provides efficient and effective quality of service for information that is time sensitive (e.g., real time data).